1988 Rolls Royce Silver Spirit Intermittent horn

SPEED88

MEMBER

1988 ROLLS ROYCE SILVER SPIRIT

V8

2WD

AUTOMATIC

55,000 MILES

Horn of car works correctly when stationary. When steering wheel turns the horn sounds intermittently. Relay has been changed, connection to the horn button on the wheel is correctly islolated. Can you please assist where the fault maybe please.